Radial impulse engine, pump, and compressor systems, and associated methods of operation

ABSTRACT

Radial impulse engine, pump, and compressor systems are disclosed herein. In one embodiment of the invention, an engine includes a first end wall portion spaced apart from a second end wall portion to at least partially define a combustion chamber therebetween. In this embodiment, the engine further includes a plurality of movable wall portions disposed between the first and second end wall portions. Each movable wall portion includes a cylindrical surface extending at least partially between a distal edge portion and a pivot axis. Upon ignition in the combustion chamber, the distal edge portion of each movable wall portion slides across the cylindrical surface of the adjacent movable wall portion as the movable wall portions pivot outwardly in unison about their respective pivot axes.

CROSS-REFERENCE TO RELATED APPLICATIONS INCORPORATED BY REFERENCE

The present application claims priority to U.S. Provisional PatentApplication No. 60/676,017, filed Apr. 29, 2005, and U.S. ProvisionalPatent Application No. 60/719,631, filed Sep. 21, 2005. U.S. ProvisionalPatent Application No. 60/676,017 and U.S. Provisional PatentApplication No. 60/719,631 are incorporated herein in their entiretiesby reference.

The present application is related to copending U.S. patent applicationSer. No. [Attorney Docket No. 56677.8001.US02], entitled “RADIAL IMPULSEENGINE, PUMP, AND COMPRESSOR SYSTEMS, AND ASSOCIATED METHODS OFOPERATION,” filed concurrently herewith; copending U.S. patentapplication Ser. No. [Attorney Docket No. 56677.8001.US03], entitled“RADIAL IMPULSE ENGINE, PUMP, AND COMPRESSOR SYSTEMS, AND ASSOCIATEDMETHODS OF OPERATION,” filed concurrently herewith; and copending U.S.patent application Ser. No. [Attorney Docket No. 56677.8002.US01],entitled “RADIAL IMPULSE ENGINE, PUMP, AND COMPRESSOR SYSTEMS, ANDASSOCIATED METHODS OF OPERATION,” filed concurrently herewith. Each ofthe U.S. patent applications listed above is incorporated herein in itsentirety by reference.

TECHNICAL FIELD

The following disclosure relates generally to engines, pumps, andsimilar apparatuses and systems.

BACKGROUND

The efficiency of internal combustion engines is often expressed interms of thermal efficiency, which is a measure of an engine's abilityto convert fuel energy into mechanical power. Conventional internalcombustion engines with reciprocating pistons typically have relativelylow thermal efficiencies. Conventional automobile engines, for example,typically have thermal efficiencies of about 0.25, which means thatabout seventy-five percent of the fuel's energy is wasted during engineoperation. Specifically, about forty percent of the fuel's energy flowsout the exhaust pipe as lost heat, while another thirty-five percent isabsorbed by the cooling system (i.e., coolant, oil, and surrounding airflow). As a result of these losses, only about twenty-five percent ofthe fuel's energy is converted into usable power for moving the car andoperating secondary systems (e.g., charging systems, cooling systems,power-steering systems, etc.).

There are a number of reasons that conventional internal combustionengines are so inefficient. One reason is that the cylinder head andwalls of the combustion chamber absorb heat energy from the ignited fuelbut do no work. Another reason is that the ignited fuel charge is onlypartially expanded before being pumped out of the combustion chamber ata relatively high temperature and pressure during the exhaust stroke. Anadditional reason is that reciprocating piston engines produce verylittle torque through much of the piston stroke because of the geometricrelationship between the reciprocating piston and the rotatingcrankshaft.

While some advancements have been made in the field of piston enginetechnology, it appears that the practical limits of piston engineefficiency have been reached. The average fuel economy of new cars, forexample, has increased by only 2.3 miles-per-gallon (mpg) in the last 20years or so. More specifically, the average fuel economy of new cars hasincreased from 26.6 mpg in 1982 to only 28.9 mpg in 2002.

Although a number of alternatives to the conventional internalcombustion engine have been proposed, each offers only marginalimprovements. Hybrid vehicles, for example (e.g., the Toyota Prius), andalternative fuel systems (e.g., propane, natural gas, and biofuels)still use conventional reciprocating piston engines with all of theirattendant shortcomings. Electric cars, on the other hand, have limitedrange and are slow to recharge. Hydrogen fuel cells are anotheralternative, but implementation of this nascent technology is relativelyexpensive and requires a new fuel distribution infrastructure to replacethe existing petroleum-based infrastructure. Accordingly, while each ofthese technologies may hold promise for the future, they appear to beyears away from mass-market acceptance.

SUMMARY

This summary is provided for the benefit of the reader only, and doesnot limit the invention as set forth by the claims.

The present invention is directed generally toward engines, pumps, andsimilar energy conversion devices that convert thermal energy intomechanical energy or, alternatively, convert mechanical energy intofluid energy. An internal combustion engine configured in accordancewith one aspect of the invention includes a first end wall portionspaced apart from a second end wall portion to at least partially definea combustion chamber therebetween. The engine further includes first andsecond movable wall portions disposed between the first and second endwall portions. The first movable wall portion includes a first distaledge portion spaced apart from a first pivot axis. The second movablewall portion includes a second distal edge portion spaced apart from asecond pivot axis. The second movable wall portion further includes acylindrical surface extending at least partially between the seconddistal edge portion and the second pivot axis. Upon ignition in thecombustion chamber, the first distal edge portion of the first movablewall portion slides across the cylindrical surface of the second movablewall portion as the first and second movable wall portions pivotoutwardly in unison about their respective pivot axes. In one embodimentof the invention, each of the movable wall portions can additionallyinclude an aperture configured to admit at least one of air and anair/fuel mixture into the combustion chamber during engine operation.

In another aspect of the invention, the engine further includes a thirdmovable wall portion disposed between the first and second end wallportions adjacent to the second movable wall portion. Like the first andsecond movable wall portions, the third movable wall portion has a thirddistal edge portion spaced apart from a third pivot axis. In this aspectof the invention, the cylindrical surface of the first movable wallportion has a first radius of curvature, and the first, second, andthird pivot axes define a circle having a second radius of curvaturethat is at least approximately equivalent to the first radius ofcurvature.

In a further aspect of the invention, the first movable wall portion isfixedly attached to a first wrist shaft, and the second movable wallportion is fixedly attached to a second wrist shaft. In this aspect ofthe invention, the first wrist shaft is operably coupled to the secondwrist shaft to ensure that the movable wall portions move in unisonduring engine operation. In one embodiment of the invention, asynchronizing ring gear operably couples the first wrist shaft to thesecond wrist shaft for this purpose. In this embodiment, thesynchronizing ring gear is also coupled to a crankshaft for powertransmission and energy storage.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially hidden isometric view of a radial impulse engineconfigured in accordance with an embodiment of the invention.

FIG. 2 is an isometric view of the engine of FIG. 1 with a number ofcomponents removed for purposes of illustration.

FIG. 3 is a partially cut-away isometric view of the engine of FIG. 1.

FIGS. 4A-4E are a series of isometric views illustrating operation ofthe engine of FIG. 1 in a two-stroke mode in accordance with anembodiment of the invention.

FIGS. 5A-5E are a series of top views of a portion of a radial impulseengine configured in accordance with another embodiment of theinvention.

FIG. 6 is a cross-sectional top view of a portion of a radial impulseengine configured in accordance with a further embodiment of theinvention.

FIG. 7 is an isometric view of a portion of a radial impulse engineconfigured in accordance with another embodiment of the invention.

FIGS. 8A-8F are a series of top views illustrating operation of theengine of FIG. 7 in accordance with an embodiment of the invention.

FIG. 9 is an isometric view of a radial impulse engine configured inaccordance with a further embodiment of the invention.

FIG. 10 is an isometric view of the engine of FIG. 9 with a number ofcomponents removed for purposes of illustration.

FIGS. 11A-11H are a series of isometric views illustrating operation ofthe engine of FIG. 9 in a four-stroke mode in accordance with anembodiment of the invention.

FIG. 12 is an isometric view illustrating various aspects of thechordons and wrist shafts of the engine of FIGS. 1-4E.

FIG. 13 is an enlarged isometric view of one of the chordon/wrist shaftsubassemblies of the engine of FIGS. 1-4E.

FIG. 14A is an enlarged front view of a portion of the chordon of FIG.13, and FIGS. 14B and 14C are enlarged cross-sectional views taken alonglines 14B-14B and 14C-14C, respectively, in FIG. 14A.

FIG. 15 is a rear isometric view of a chordon configured in accordancewith another embodiment of the invention.

FIG. 16 is an isometric view of a portion of a radial impulse engineconfigured in accordance with a further embodiment of the invention.

FIG. 17 is a top view of the engine of FIG. 16 illustrating the extendedstroke of the associated chordons.

FIGS. 18A and 18B are top views of a portion of a radial impulse enginehaving a plurality of hinged chordons configured in accordance with anembodiment of the invention.

FIGS. 19A and 19B are top views of a portion of a radial impulse enginehaving a plurality of hinged chordons configured in accordance withanother embodiment of the invention.

FIGS. 20A and 20B are cross-sectional end views of a telescoping chordonconfigured in accordance with an embodiment of the invention.

FIG. 21 is a cross-sectional end view of a telescoping chordonconfigured in accordance with another embodiment of the invention.

FIG. 22 is a side view of a portion of a radial impulse engineillustrating a system for poppet valve actuation in accordance with anembodiment of the invention.

FIG. 23 is a side view of a portion of a radial impulse engineillustrating a system for poppet valve actuation in accordance withanother embodiment of the invention.

FIG. 24 is an isometric view of a portion of a radial impulse engineillustrating a method for controlling the flow of gaseous mixtures intoand out of an associated combustion chamber.

FIG. 25 is a partially hidden top view of a portion of a radial impulseengine having a movable valve plate configured in accordance with anembodiment of the invention.

FIG. 26 is a top view of a radial impulse engine having a cam plate fortransmitting power from a plurality of chordons to an output shaft.

FIG. 27A is a partially cut-away isometric view of a radial impulseengine that uses a duplex synchronization gear for transmitting powerfrom a plurality of chordons, and FIG. 27B is a cross-sectional viewtaken through a wrist shaft of FIG. 27A.

FIG. 28 is an isometric view of a portion of a power unit having a firstradial impulse engine operably coupled to a second radial impulse enginein accordance with an embodiment of the invention.

FIG. 29 is an isometric view of a portion of a power unit configured inaccordance with another embodiment of the invention.

FIG. 30 is a partially schematic side view of a power unit configured inaccordance with a further embodiment of the invention.

FIGS. 31A-31C are a series of top views illustrating a method ofoperating the power unit of FIG. 30.

FIGS. 32A and 32B are top views of a radial impulse steam engineconfigured in accordance with an embodiment of the invention.

FIGS. 33A and 33B are top views of a radial impulse steam engineconfigured in accordance with another embodiment of the invention.

DETAILED DESCRIPTION

The following disclosure provides a detailed description of a number ofdifferent engine, pump, and compressor systems, as well as a number ofdifferent methods for operating such systems. Certain details are setforth in the following description to provide a thorough understandingof various embodiments of the invention. Other details describingwell-known structures and systems often associated with internalcombustion engines, steam engines, pumps, and similar devices are notset forth below, however, to avoid unnecessarily obscuring thedescription of the various embodiments of the invention.

Many of the details, dimensions, angles, and other features shown in theFigures are merely illustrative of particular embodiments of theinvention. Accordingly, other embodiments can have other details,dimensions, angles, and/or features without departing from the spirit orscope of the present invention. Furthermore, additional embodiments ofthe invention can be practiced without several of the details describedbelow.

In the Figures, identical reference numbers identify identical or atleast generally similar elements. To facilitate the discussion of anyparticular element, the most significant digit or digits of anyreference number refer to the Figure in which that element is firstintroduced. For example, element 110 is first introduced and discussedwith reference to FIG. 1.

I. Radial Impulse Internal Combustion Engines

FIG. 1 is a partially hidden isometric view of a radial impulse engine100 (“engine 100”) configured in accordance with an embodiment of theinvention. In one aspect of this embodiment, the engine 100 includes acylindrical scavenging barrel 102 extending between a first end plate104 a and a second end plate 104 b. An intake manifold 106 extendsaround the scavenging barrel 102 and includes a first inlet 108 aopposite a second inlet 108 b. The inlets 108 are configured to provideair to the scavenging barrel 102 during operation of the engine 100.

In another aspect of this embodiment, the engine 100 further includes afirst exhaust manifold 110 a attached to the first end plate 104 a and asecond exhaust manifold 110 b attached to the second end plate 104 b.The first exhaust manifold 110 a is configured to direct exhaust gasesaway from the scavenging barrel 102 through a first exhaust outlet 112 aand a second exhaust outlet 112 b. The second exhaust manifold 110 b issimilarly configured to direct exhaust gases away from the scavengingbarrel 102 through a third exhaust outlet 112 c and a fourth exhaustoutlet 112 d. Although not shown in FIG. 1, the exhaust outlets 112 canbe connected to a muffler and/or an emission control device if desiredfor acoustic attenuation and/or exhaust gas cleaning, respectively.

As described in detail below, fuel can be provided to the engine 100 ina number of different ways. In the illustrated embodiment, for example,fuel is provided to a first fuel injector (not shown in FIG. 1) via afirst fuel line 116 a and to a second fuel injector (also not shown) viaa second fuel line 116 b. Although this embodiment of the engine 100utilizes fuel injection, in other embodiments, the engine 100 canutilize other forms of fuel delivery. Such forms can include, forexample, carburetors, fuel-injected throttle bodies, or similar devicespositioned in flow communication with the first inlet 108 a and thesecond inlet 108 b of the intake manifold 106.

Once fuel has been injected into the engine 100, it can be ignited in anumber of different ways as well. In the illustrated embodiment, forexample, a first spark plug (not shown in FIG. 1) operably connected toa first ignition wire 114 a, and by a second spark plug (also not shownin FIG. 1) operably connected to a second ignition wire 114 b ignite thefuel. In other embodiments, other devices (e.g., glow plugs) can be usedfor intake charge ignition or, alternatively, the ignition devices canbe omitted and the intake charge can be ignited by compression ignition.

FIG. 2 is an isometric view of the engine 100 with the intake manifold106, the exhaust manifolds 110, and a number of other components removedfor purposes of illustration. In one aspect of this embodiment, theengine 100 includes a plurality of movable wall portions 240 (identifiedindividually as movable wall portions 240 a-f) positioned around acombustion chamber 203. For ease of reference, the movable wall portions240 are referred to herein as “chordons.” In the illustrated embodiment,each of the chordons 240 is a movable member that includes a curved face244, a distal edge portion 242, and a plurality of transfer ports 224(identified individually as transfer ports 224 a-b). Each of thechordons 240 is fixedly attached to a corresponding wrist shaft 220(identified individually as wrist shafts 220 a-f). The wrist shafts 220are pivotally supported by the first end plate 104 a and the second endplate 104 b shown in FIG. 1. As described in greater detail below,during operation of the engine 100, the chordons 240 pivot back andforth in unison about their respective wrist shafts 220. In the process,the distal edge portion 242 of each chordon 240 slides back and forthacross the adjacent chordon face 244, thereby sealing the combustionchamber 203 without detrimental binding or interference.

In another aspect of this embodiment, each wrist shaft 220 carries afirst timing gear 222 (identified individually as first timing gears 222a-f) on one end and a second timing gear 223 (identified individually assecond timing gears 223 a-f) on the other end. Each of the first timinggears 222 is operably engaged with a first ring gear 228 a, and each ofthe second timing gears 223 is similarly engaged with a second ring gear228 b. The ring gears 228 synchronize motion of the chordons 240 duringoperation of the engine 100.

In a further aspect of this embodiment, a crank-arm 229 extendsoutwardly from the first ring gear 228 a and is pivotally coupled to aconnecting rod 262. The connecting rod 262 is in turn pivotally coupledto a crankshaft 270. The crankshaft 270 can include one or moreflywheels 272 of sufficient mass to drive the chordons 240 through thecompression (inward) portion of their cyclic motion. Although only onecrankshaft assembly is illustrated in FIG. 2, in other embodiments,additional crank-arms, connecting rods, and/or crankshafts can be usedif necessary for storing additional kinetic energy or for structuraland/or dynamic reasons. For example, in another embodiment, a secondcrank-arm extends outwardly from the second ring gear 228 b and can bepivotally coupled to the crankshaft 270 (or another crankshaft) by meansof a second connecting rod.

FIG. 3 is a partially cut-away isometric view of the engine 100 with thechordons 240 rotated to an outward position. In one aspect of thisembodiment, the engine 100 includes a plurality of one-way valves 326(identified individually as one-way valves 326 a-f) positioned aroundthe scavenging barrel 102 adjacent to corresponding chordons 240. Theone-way valves 326 can include reed valves or similar devices configuredto pass air (or an air/fuel mixture) into, but not out of, thescavenging barrel 102.

In another aspect of this embodiment, the engine 100 further includes aplurality of exhaust valves 330 (identified individually as exhaustvalves 330 a-l). The exhaust valves 330 a-f extend through the first endplate 104 a, and the exhaust valves 330 g-l extend through the secondend plate 104 b. Each of the exhaust valves 330 seats in a correspondingexhaust port 337, and is held closed by a corresponding coil spring 335.An actuator plate 336 presses against the coil springs 335 to move theexhaust valves 330 away from the respective end plate 104 and open theexhaust ports 337. Opening the exhaust ports 337 in this manner allowsexhaust gases to flow out of the combustion chamber 203 through theadjacent exhaust manifold 110.

In a further aspect of this embodiment, the engine 100 also includesfirst and second fuel injectors 334 a and 334 b, and first and secondigniters 332 a and 332 b (e.g., spark plugs). The first and second fuelinjectors 334 a and 334 b are carried by the first and second end plates104 a and 104 b, respectively, and are configured to receive fuel fromthe first and second fuel lines 116 a and 116 b of FIG. 1, respectively.The first and second igniters 332 a and 332 b are carried by the firstand second end plates 104 a and 104 b adjacent to the first and secondfuel injectors 334 a and 334 b, respectively. In the illustratedembodiment, the first and second igniters 332 a and 332 b are alignedwith a central axis 301 of the engine 100, and are configured to receiveelectrical voltage via the first and second ignition wires 114 a and 114b of FIG. 1, respectively.

FIGS. 4A-4E are a series of isometric views illustrating operation ofthe engine 100 in a two-stroke mode in accordance with an embodiment ofthe invention. A number of engine components have been omitted fromFIGS. 4A-4E to facilitate the discussion that follows. Referring firstto FIG. 4A, in this view the chordons 240 are at the innermost part oftheir pivotal stroke which, for ease of reference, can be referred to as“top dead center.” The top dead center position of the chordons 240corresponds to top dead center position of the crankshaft 270. At thispoint in the cycle, the fuel injectors 334 (FIG. 3) have injected fuelinto the combustion chamber 203, and the igniters 332 (FIG. 3) haveignited the compressed air/fuel mixture. The resulting combustion drivesthe chordons 240 outwardly, causing the wrist shafts 220 to rotate in acounterclockwise direction about their respective axes. As the wristshafts 220 rotate in the counterclockwise direction, the timing gears222/223 drive the ring gears 228 in a clockwise direction. As the firstring gear 228 a rotates, it transmits power from the chordons 240 to thecrankshaft 270 via the crank-arm 229.

Referring next to FIG. 4B, when the chordons 240 reach a point in theiroutward stroke just beyond the exhaust valves 330, the exhaust valves330 begin opening into the combustion chamber 203. This allows exhaustgases to begin flowing out of the combustion chamber 203 through theexhaust ports 337 (FIG. 3). As the chordons 240 continue movingoutwardly, they compress the air trapped between them and the scavengingbarrel 102. This compressed air is allowed to flow into the combustionchamber 203 once the distal edge portion 242 of each chordon 240 slidespast the transfer ports 224 in the adjacent chordon 240. This incomingair helps to push the exhaust gases out of the combustion chamber 203through the exhaust ports 337. When the chordons 240 reach the outermostpart of their pivotal stroke (i.e., the “bottom dead center” position)as shown in FIG. 4C, the exhaust valves 330 are fully open. From here,the kinetic energy of the crankshaft flywheels 272 causes the chordons240 to reverse direction and begin moving inwardly toward the top deadcenter position of FIG. 4A.

Referring to FIG. 4D, as the chordons 240 continue moving inwardlytoward the top dead center position, they compress the intake charge andcontinue to push the exhaust gases out of the combustion chamber 203through the exhaust ports 337. The exhaust valves 330 fully retract,however, before the chordons 240 reach them to avoid contact. As thechordons 240 continue moving inwardly, they create a vacuum in the spacebetween them and the scavenging barrel 102. This vacuum draws fresh airinto the scavenging barrel 102 through the one-way valves 326. This airwill be compressed by the next outward stroke of the chordons 240 beforeflowing into the combustion chamber 203 through the transfer ports 224.

In FIG. 4E, the chordons 240 have returned to the top dead centerposition from which they started in FIG. 4A. At this point in the cycle,the intake charge in the combustion chamber 203 is fully compressed. Asdiscussed above with reference to FIG. 4A, the fuel injectors 334 caninject fuel into the combustion chamber 203 at or about this time forignition by the igniters 232. When this occurs, the cycle describedabove with reference to FIGS. 4A-4D repeats.

Although the embodiment of the invention described above uses fuelinjection, in other embodiments the engine 100 can use other forms offuel delivery. Such forms can include, for example, carburetors orfuel-injected throttle bodies providing an air/fuel mixture to thecombustion chamber 203 through the inlets 108 (FIG. 1) of the intakemanifold 106 (FIG. 1). While the engine 100 will operate satisfactorilywith carburetors, fuel injection may offer certain advantages, such asbetter fuel economy and lower hydrocarbon emissions.

FIGS. 5A-5E are a series of top views of a portion of a radial impulseengine 500 (“engine 500”) configured in accordance with anotherembodiment of the invention. Referring first to FIG. 5A, many featuresof the engine 500 can be at least generally similar in structure andfunction to corresponding features of the engine 100 described abovewith reference to FIGS. 1-4E. In this particular embodiment, however,the engine 500 does not include a scavenging barrel or the associatedone-way valves. Furthermore, although the engine 500 does include aplurality of chordons 540 (identified individually as chordons 540 a-f),the chordons 540 lack transfer ports (such as the transfer ports 224described above with reference to FIGS. 2-4E). The engine 500 does,however, include an intake valve 531 in a first end plate 504 a and anexhaust valve 530 in a second end plate 504 b. The intake valve 531 andthe exhaust valve 530 are aligned with a central axis 501 of acombustion chamber 503. A fuel injector 534 and an igniter 532 extendinto the combustion chamber 503 adjacent to the intake valve 531.

The engine 500 can operate in both two-stroke and four-stroke modes. Intwo-stroke mode, the igniter 532 ignites a compressed intake charge whenthe chordons 540 are at or near the top dead center position illustratedin FIG. 5A. At this point in the cycle, the intake valve 531 and theexhaust valve 530 are fully closed, and the resulting combustionpressure drives the chordons 540 outwardly. When the chordons 540 reachthe position illustrated in FIG. 5B, the exhaust valve 530 begins toopen, enabling the expanding exhaust gases to start flowing out of thecombustion chamber 503.

When the chordons 540 reach the position illustrated in FIG. 5C, theexhaust valve 530 is fully, or near-fully, open. At this point in thecycle, the intake valve 531 begins to open, allowing pressurized air(from, for example, an accessory scavenging blower) to flow into thecombustion chamber 503. The outward motion of the chordons 540facilitates the flow of pressurized air into the combustion chamber 503,which helps to push the exhaust gasses out of the combustion chamber 503past the open exhaust valve 530.

When the chordons 540 reach the bottom dead center position shown inFIG. 5D, both the exhaust valve 530 and the intake valve 531 are fullyopen. As the chordons 540 begin moving inwardly from this point, theintake valve 531 starts to close. When the chordons 540 reach theposition illustrated in FIG. 5E, the intake valve 531 is fully, ornear-fully, closed. The exhaust valve 530, however, is just starting toclose. As a result, the chordons 540 continue pushing the exhaust gasesout of the combustion chamber 503 as they proceed inwardly, compressingthe intake charge. When the chordons 540 reach the top dead centerposition shown in FIG. 5A, both the exhaust valve 530 and the intakevalve 531 are fully closed. At or about this time, the fuel injector 534injects fuel into the combustion chamber 503 for ignition by the igniter532. When this occurs, the cycle described above can repeat.

Although the embodiment of the engine 500 described above utilizes fuelinjection, those of ordinary skill in the relevant art will appreciatethat the engine 500 or variations thereof can be readily adapted tooperate with a carburetor or similar device that introduces an air/fuelmixture into the combustion chamber 503 via the intake valve 531.Furthermore, although the engine 500 only includes a single intake valveand a single exhaust valve, in other embodiments, engines at leastgenerally similar in structure and function to the engine 500 caninclude a plurality of intake valves in the first end plate 504 a and aplurality of exhaust valves in the second end plate 504 b. In stillfurther embodiments, engines at least generally similar in structure andfunction to the engine 500 can include both intake and exhaust valves oneach of the end plates 504. In such embodiments, however, thecorresponding intake/exhaust manifolds may be somewhat complicated.

FIG. 6 is a cross-sectional top view of a portion of a radial impulseengine 600 (“engine 600”) configured in accordance with a furtherembodiment of the invention. Many features of the engine 600 are atleast generally similar in structure and function to correspondingfeatures of the engine 100 described above with reference to FIGS. 1-4E.For example, the engine 600 includes a plurality of chordons 640(identified individually as chordons 640 a-f) and a plurality ofcorresponding wrist shafts 620 (identified individually as wrist shafts620 a-f). The wrist shafts 620 enable the chordons 640 to pivot betweenfirst and second end plates (not shown). As in the engine 100, each endplate includes a plurality of exhaust ports 630 (identified individuallyas exhaust ports 630 a-f), and each end plate carries a fuel injector634 and an igniter 632 which extend into an adjacent combustion chamber603.

Unlike the chordons 240 of the engine 100, the chordons 640 of theengine 600 reciprocate through an arc of about 180 degrees during normaloperation. To accommodate this motion, the engine 600 further includes ascavenging barrel 602 with a plurality of individual chordon chambers605 a-f. In the illustrated embodiment, each chordon chamber 605receives air from an associated one-way valve 626 (identifiedindividually as one-way valves 626 a-f). The one-way valves 626 flow airinto the chordon chambers 605 via a back wall 601. A transfer port 650extends from an inlet 651 on each back wall 601 to an outlet 653 on anadjacent front wall 607.

In operation, the fuel injectors 634 spray fuel into the combustionchamber 603 when the chordons 640 are at or near a first position P₁(i.e., a top dead center position). The fuel mixes with compressed airin the combustion chamber 603 and is ignited by the igniters 632. Theresulting combustion drives the chordons 640 outwardly from the firstposition P₁ to a second position P₂. As the chordons 640 approach thesecond position P₂, they allow the exhaust gases to begin flowing out ofthe combustion chamber 603 through the exposed exhaust ports 630. As thechordons 640 continue moving outwardly from the second position P₂toward a third position P₃, they compress the air trapped in theirrespective chordon chambers 605. As the chordons 640 continue movingtoward a fourth position P₄, however, they drive the compressed air backinto the chordon chambers 605 through the transfer ports 650. Thisincoming charge helps to push the exhaust gases out of the combustionchamber 603 through the exhaust ports 630.

As the chordons 640 reverse direction and begin moving inwardly from thefourth position P₄ (i.e., the bottom dead center position), theycompress the intake charge which further helps to drive the exhaustgases out of the combustion chamber 603. In addition, this motion alsodraws new air into the chordon chambers 605 through the one-way valves626. Further inward motion of the chordons 640 continues to compress theintake charge and push the exhaust gases out of the combustion chamber603 through the exhaust ports 630. When the chordons 640 arrive atposition P₁, the fuel injectors 634 again inject fuel into thecombustion chamber 603 for ignition by the igniters 632, causing thecycle described above to repeat.

Various aspects of the engine 600 can be different from those describedabove without departing from the spirit or scope of the presentinvention. For example, in another embodiment, the transfer ports 650can be positioned in one or both of the end plates (not shown). In afurther embodiment, the exhaust ports 630 can be movable relative totheir respective end plates to vary the exhaust timing and change engineperformance characteristics accordingly. One way to vary the exhausttiming is to utilize controllable shutter valves or similar devices tovary the port positions and/or size. In yet other embodiments, sleevevalves or similar devices can be used to actively change the relativepositions of the one-way valves 626 and/or the transfer port outlets 653to alter intake timing as desired.

FIG. 7 is an isometric view of a portion of a radial impulse engine 700(“engine 700”) configured in accordance with another embodiment of theinvention. Many features of the engine 700 are at least generallysimilar in structure and function to corresponding features of theengine 100 described above with reference to FIGS. 1-4E. For example,the engine 700 includes a plurality of symmetrical chordons 740(identified individually as chordons 740 a-f) and a plurality ofcorresponding wrist shafts 720 (identified individually as wrist shafts720 a-f). As in the engine 100, the wrist shafts 720 enable the chordons740 to pivot between a first end plate 704 a and a second end plate 704b. As described in greater detail below, however, in this particularembodiment the chordons 740 rotate completely around their respectivewrist shafts 720 during engine operation, rather than reciprocatingbackward and forward. To facilitate this motion, the first end plate 704a includes a first charge receiver 754 a and the second end plate 704 bincludes a second charge receiver 754 b. The charge receivers 754 arerecessed with respect to a combustion chamber 703, and each carries afuel injector 734 and a corresponding igniter 732.

FIGS. 8A-8F are a series of top views illustrating operation of theengine 700 in accordance with an embodiment of the invention. In FIG.8A, the chordons 740 are moving inwardly and have just begun compressingthe air in the combustion chamber 703. As the chordons 740 approach theposition shown in FIG. 8B, the air in the combustion chamber 703 and theadjacent charge receivers 754 is highly compressed. As the chordons 740continue rotating toward the center of the combustion chamber 703, thevolume of the combustion chamber 703 approaches the vanishing point,forcing the air into the adjacent charge receivers 754. At or about thistime, the fuel injectors 734 spray fuel into the charge receivers 754,and the resulting air/fuel mixture is ignited by the igniters 732.

Referring next to FIG. 8C, as the ignited air/fuel mixture begins toexpand, it drives the chordons 740 outwardly in the clockwise directiontoward the position shown in FIG. 8D. Although not shown in FIGS. 8A-8F,the engine 700 can include a crankshaft or other suitable power-take-outdevice to harness the power from the chordons 740. As the chordons 740approach the position shown in FIG. 8E, they let the exhaust gases flowout of the combustion chamber 703. From here, the chordons 740 continuetheir clockwise rotation, drawing the exhaust gases out of thecombustion chamber 703 and circulating new air into the combustionchamber 703. When the chordons 740 reach the position shown in FIG. 8F,the cycle repeats.

FIG. 9 is an isometric view of a radial impulse engine 900 (“engine900”) configured in accordance with another embodiment of the invention.Many features of the engine 900 can be at least generally similar instructure and function to corresponding features of the engine 100described above with reference to FIGS. 1-4E. In the particularembodiment of FIG. 9, however, the engine 900 includes an enclosure 905extending between a first end plate 904 a and a second end plate 904 b.The engine 900 further includes an intake manifold 906 positioned on thefirst end plate 904 a and an exhaust manifold 910 positioned on thesecond end plate 904 b. The intake manifold 906 includes a first inlet908 a opposite a second inlet 908 b. The inlets 908 are configured toprovide an air/fuel mixture to the engine 900 from an associatedcarburetor, fuel-injected throttle body, or other fuel delivery device.In other embodiments, the engine 900 can be configured to operate with afuel injection system similar to one or more of the fuel injectionsystems described above. The exhaust manifold 910 is configured todirect exhaust gases away from the engine 900 through a first exhaustoutlet 912 a and a second exhaust outlet 912 b. A suitable mufflerand/or emission control device can be connected to the exhaust outlets912 if desired for noise suppression and/or exhaust gas cleansing.

The engine 900 further includes a first ignition wire 916 a and a secondignition wire 916 b. Each of the ignition wires 916 is operablyconnected to a corresponding igniter or spark plug (not shown in FIG. 9)carried by one of the end plates 904.

FIG. 10 is an isometric view of the engine 900 with the enclosure 905and a number of other components removed for purposes of illustration.As mentioned above, many features of the engine 900 are at leastgenerally similar in structure and function to the correspondingfeatures of the engine 100 described above with reference to FIGS. 1-4E.For example, the engine 900 includes a plurality of movable chordons1040 a-f and a plurality of corresponding wrist shafts 1020 a-f. Theengine 900 also includes a first igniter 1032 a positioned at one end ofa combustion chamber 1003, and a second igniter 1032 b positioned at theother end of the combustion chamber 1003. The chordons 1040 are operablycoupled to a crankshaft 1070 for power take out.

Unlike the engine 100, however, the engine 900 lacks a scavenging barreland the associated one-way valves. Instead, the engine 900 utilizes aplurality of intake valves 1031 a-f that are carried by the first endplate 904 a (FIG. 9). As described in-detail below, the intake valves1031 are configured to open at the appropriate times during engineoperation to admit an air/fuel mixture from the intake manifold 906(FIG. 9) into the combustion chamber 1003 for subsequent ignition by theigniters 1032. In an alternate embodiment, the engine 900 can includeone or more fuel injectors positioned proximate to the igniters 1032 fordirect fuel injection. With direct fuel injection, the intake valves1031 can be used to introduce air into the combustion chamber 1003rather than an air/fuel mixture.

The engine 900 further includes a plurality of exhaust valves 1030 g-lthat are carried by the second end plate 904 b (FIG. 9). As described indetail below, the exhaust valves 1030 are configured to open at theappropriate times during engine operation to allow the exhaust gases toflow out of the combustion chamber 1003 through the exhaust manifold 910(FIG. 9).

FIGS. 11A-11H are a series of isometric views illustrating operation ofthe engine 900 in a four-stroke mode in accordance with an embodiment ofthe invention. In this embodiment, the cycle begins with the chordons1040 in a top dead center position at the end of an exhaust stroke, asillustrated in FIG. 11A. When the chordons 1040 are in this position,both the intake valves 1031 and the exhaust valves 1030 are fullyclosed. From here, the rotational momentum of the crankshaft 1070 causesthe chordons 1040 to move outwardly toward the position shown in FIG.11B. As the chordons 1040 approach this position, the intake valves 1031begin to open, allowing an air/fuel mixture to be drawn into thecombustion chamber 1003 from the intake manifold 906 (FIG. 9). When thechordons 1040 reach the bottom dead center position illustrated in FIG.11C, the intake valves 1031 are fully open to maximize intake flow. Atthis position, the rotation of the crankshaft 1070 causes the chordons1040 to stop and reverse direction.

As the chordons 1040 move inwardly toward the position shown in FIG.11D, the intake valves 1031 close to avoid chordon contact. As thechordons 1040 continue moving inwardly, they compress the intake chargein the combustion chamber 1003. When the chordons 1040 reach the topdead center position shown in FIG. 11E, the igniters 1032 (FIG. 10)ignite the intake charge. The resulting combustion pressure drives thechordons 1040 outwardly, transmitting power to the crankshaft 1070. Whenthe chordons 1040 reach the position illustrated in FIG. 11F, theexhaust valves 1030 start to open, allowing the exhaust gases to flowout of the combustion chamber 1003 through the exhaust manifold 910(FIG. 9). When the chordons 1040 reach the bottom dead center positionshown in FIG. 11G, the exhaust valves 1030 are fully open to maximizeexhaust outflow. At this position, the rotation of the crankshaft 1070causes the chordons 1040 to stop and reverse direction.

As the chordons 1040 move inwardly toward the position shown in FIG.11H, they drive the exhaust gases out of the combustion chamber 1003past the open exhaust valves 1030. The exhaust valves 1030 are closingat this time, however, so that they will be fully closed just before thechordons 1040 reach them to avoid any detrimental contact. When thechordons 1040 reach the top dead center position of FIG. 11A, the cycledescribed above repeats.

Although the engine 900 utilizes multiple intake and exhaust valves, inother embodiments, other engines at least generally similar in structureand function to the engine 900 can utilize a single intake valve on oneend plate and a single exhaust valve on the opposing end plate. Infurther embodiments, other similar engines can utilize commingledexhaust and intake valves on one or both end plates. In yet otherembodiments, a four-stroke engine similar to the engine 900 describedabove can operate with unidirectional rotation of the chordons 1040about their respective wrist shafts 1020. In such embodiments, chordonmotion can be at least generally similar to the chordon motion describedabove with reference to FIGS. 8A-8F.

One feature of the radial impulse engines described above with referenceto FIGS. 1-11H is that the combustion chamber has a higher ReactiveSurface Ratio (RSR) than comparable internal combustion engines withreciprocating pistons. This is because the combustion chamber of thepresent invention expands exponentially, with the ignited fuel chargedoing work against each of the individual chordons during their outwardstroke. In contrast, the combustion chamber of a conventionalreciprocating piston engine expands only linearly, with the ignited fuelcharge only doing work against the top surface of the piston and not thefixed cylinder walls. One advantage of the high RSR of the presentinvention is that it increases the amount of shaft work extracted fromthe fuel as a result of the combustion process. In this regard, it isexpected that radial impulse engines configured in accordance withembodiments of the invention can achieve thermal efficiencies of about0.50 or more, which corresponds to a 100% increase over conventionalinternal combustion engines.

Another feature of the radial impulse engines described above is thatoutward chordon motion “hyper-expands” the exhaust gases during thepower stroke. This hyper-expansion has the advantage of significantlyreducing exhaust gas temperatures. As a result, the engine runssignificantly cooler, leading to less wear and tear on the internalengine parts over time. In addition, the lower operating temperaturesallow the use of a smaller capacity cooling system than conventionalinternal combustion engines. One advantage of the smaller cooling systemis that it draws less power from the engine during operation than acomparable cooling system for a conventional engine.

Yet another feature of the radial impulse engines described above isthat they have fewer parts than conventional internal combustion enginesof comparable capacity and output. As a result, the radial impulseengines of the present invention can be made smaller and lighter andgenerally more compact than conventional engines. This feature enablescars and other vehicles that use the engines of the present invention tobe made smaller and lighter than their conventional counterparts and tohave correspondingly better fuel efficiency. The reduction in movingparts also results in a reduction in overall operating friction, whichagain leads to increased fuel efficiency.

II. Chordon Features

FIG. 12 is an isometric view illustrating various aspects of thechordons 240 and the wrist shafts 220 from the engine 100 describedabove with reference to FIGS. 1-4E. In one aspect of this embodiment,the wrist shafts 220 have pivot axes P_(a)-P_(f) that define a circle C.The circle C has a first radius of curvature R₁. In another aspect ofthis embodiment, each of the chordon faces 244 has a second radius ofcurvature R₂ relative to a centerline axis CL. The centerline axis CL isparallel to the wrist shaft pivot axes P_(a)-P_(f). In this particularembodiment, the second radius of curvature R₂ is equivalent to, or atleast approximately equivalent to, to the first radius of curvature R₁.

For radial impulse engines having six chordons, making the radius ofcurvature of the chordon face 244 at least approximately equivalent tothe radius of curvature of the circle passing through the wrist shaftpivot axes P_(a)-P_(f) has been shown to facilitate continuouschordon-to-chordon sliding contact during chordon reciprocation withoutdetrimental binding. As described in greater detail below, however, inother embodiments radial impulse engines configured in accordance withvarious aspects of the invention can include more or fewer chordonshaving other configurations.

FIG. 13 is an enlarged isometric view of one of the chordon/wrist shaftsubassemblies from the engine 100 described above with reference toFIGS. 1-4E. In one aspect of this embodiment, the chordon 240 caninclude one or more coolant passages 1346 that circulate coolant throughthe chordon 240 during engine operation. In the illustrated embodiment,the coolant passages 1346 receive coolant from an inlet 1348 apositioned toward one end of the wrist shaft 220, and discharge theheated coolant through an outlet 1348 b positioned toward the oppositeend of the wrist shaft 220.

In another aspect of this embodiment, the chordon 240 can furtherinclude a first pressure control seal 1356 a extending along a first endedge portion 1351 a, a second pressure control seal 1356 b extendingalong a second end edge portion 1351 b, and a third pressure controlseal 1356 c extending along the distal edge portion 242. The pressurecontrol seals 1356 reduce pressure leaks between the chordon 240 andadjacent surfaces during operation of the engine 100. For example, thefirst pressure control seal 1356 a seals the gap between the chordon 240and the first end plate 104 a (not shown), and the second pressurecontrol seal 1356 b seals the gap between the chordon 240 and the secondend plate 104 b (also not shown). The third pressure control seal 1356 cseals the gap between the chordon 240 and the adjacent chordon faceduring engine operation.

In addition to the pressure control seals 1356, the chordon 240 can alsoinclude a first oil control seal 1354 a extending along a first endsurface 1353 a, and a second oil control seal 1354 b extending across asecond end surface 1353 b. Both of the oil control seals 1354, as wellas the third pressure control seal 1356 c, can be configured to receivelubrication from an oil galley 1350 passing through the chordon 240. Inthe illustrated embodiment, the oil galley 1350 receives oil from aninlet 1352 a positioned toward one end of the wrist shaft 220, anddischarges the oil through an outlet 1352 b positioned toward theopposite end of the wrist shaft 220. During engine operation, the oilcontrol seals 1354 and the third pressure control seal 1356 c canprovide lubrication between the chordon 240 and the adjacent surfaces toreduce friction and minimize engine wear.

FIG. 14A is an enlarged front view of a portion of the chordon 240 ofFIG. 13. FIGS. 14B and 14C are enlarged cross-sectional views takenalong lines 14B-14B and 14C-14C, respectively, in FIG. 14A. Referring toFIGS. 14A-C together, in one aspect of this embodiment, each of thepressure control seals 1356 and each of the oil control seals 1354 canbe made from flat pieces of metal or other suitable material. Wheninstalled in corresponding seal grooves 1358 (identified individually asseal grooves 1358 a-c), the first pressure control seal 1356 a takes theshape of a conic section, while the first oil control seal 1354 a andthe third pressure control seal 1356 c remain flat.

In another aspect of this embodiment, a plurality of springs 1362 a-c(e.g., metallic springs) can be disposed in the grooves 1358 a-c,respectively, to press the corresponding seals 1354/1356 outwardlyagainst adjacent surfaces and maintain an adequate seal during engineoperation. Alternatively, in another embodiment, each of the seals1354/1356 can be pressurized by combustion chamber gases flowing throughback-ports (not shown) in the chordon 240.

The various chordon features described above represent only a few of thedifferent approaches that can be used to solve the inherent internalcombustion engine problems of cooling, lubrication, andcombustion-chamber sealing. Accordingly, in other embodiments, otherapproaches can be used to solve these problems. In one such embodiment,for example, the lubricating medium can provide chordon cooling, therebydispensing with the need for a separate cooling system. In anotherembodiment, nonmetallic O-ring type seals, such as Teflon® seals, can beused for chordon sealing.

FIG. 15 is a rear isometric view of a chordon 1540 configured inaccordance with another embodiment of the invention. Many features ofthe chordon 1540 can be at least generally similar in structure andfunction to corresponding features of the chordon 240 described abovewith reference to FIGS. 13-14C. For example, the chordon 1540 includes acurved face 1544 that is swept by an adjacent chordon during engineoperation. In one aspect of this particular embodiment, however, thechordon 1540 further includes a plurality of cooling fins 1548 on abackside or unswept surface 1545. The cooling fins 1548 increase thesurface area of the unswept surface 1545 to improve the heat transferbetween the chordon 1540 and the cool intake charge during engineoperation. Cooling the chordon 1540 in the foregoing manner can minimizeheat input to the chordon cooling system, thereby increasing overallengine efficiency.

FIG. 16 is an isometric view of a portion of a radial impulse engine1600 (“engine 1600”) configured in accordance with a further embodimentof the invention. The engine 1600 includes a plurality of chordons 1640a-f fixedly attached to corresponding wrist shafts 1620 a-f. Thechordons 1640 and the wrist shafts 1620 are at least generally similarin structure and function to their counterparts described above. Thechordons 1640 differ in one particular aspect, however, in that theyeach include a curved face 1644 that extends from a distal edge portion1642 to a proximal edge portion 1643 positioned beyond a pivot axis 1621of the corresponding wrist shaft 1620.

In another aspect of this embodiment, the chordons 1640 can also include“sub-axial” transfer ports 1624 a-b that extend through the chordon 1640outboard of the pivot axis 1621 of the corresponding wrist shaft 1620.As illustrated in FIG. 16, in selected embodiments, movable shuttervalves 1666 (identified individually as a first shutter valve 1666 a anda second shutter valve 1666 b) can be used to adjust the size and/oropening point of the transfer ports 1624 during engine operation.Varying the port size and/or timing in this manner can be used to alterengine performance characteristics as desired.

FIG. 17 is a top view of the engine 1600 illustrating the extendedstroke of the chordons 1640. As this view shows, each of the chordons1640 includes a distal edge portion 1642 that sweeps beyond the pivotaxis 1621 of the adjacent wrist shaft 1620 as the chordons 1640 pivotoutwardly from a top dead center position P₁ to a bottom dead centerposition P₂. Extending the chordon stroke in the foregoing mannerresults in greater wrist shaft rotation and smoother power delivery.

Although the embodiments of the invention described above utilize“one-piece” chordons, in other embodiments (such as the embodimentsdescribed below), other radial impulse engines configured in accordancewith the present invention can utilize multi-piece hinged and/ortelescoping chordons.

FIGS. 18A and 18B are top views of a portion of a radial impulse engine1800 (“engine 1800”) having a plurality of hinged chordons 1840 a-hconfigured in accordance with an embodiment of the invention. Referringfirst to FIG. 18A, in this embodiment each of the chordons 1840 caninclude a body portion 1841 (identified individually as body portions1841 a-h) fixedly attached to a corresponding wrist shaft 1820(identified individually as wrist shafts 1820 a-h), and a hingedextension 1842 (identified individually as hinged extensions 1842 a-h)pivotally attached to the body portions 1841. A control link 1843 can beoperably coupled to each of the hinged extensions 1842 to controlmovement of the hinged extensions 1842 as the chordons 1840 pivotoutwardly from the top dead center position illustrated in FIG. 18A tothe bottom dead center position illustrated in FIG. 18B.

In one aspect of this embodiment, the engine 1800 includes eightchordons 1840, and each of the body portions 1841 has a length L that isat least approximately equivalent to a chord distance D between adjacentwrist shaft pivot axes. In other embodiments, however, other radialimpulse engines can have more or fewer hinged chordons, and each of thechordons can have corresponding body portions with lengths that aregreater or less than the chord length between adjacent wrist shaft pivotaxes. In such embodiments, however, it may be necessary to utilizemultiple hinged chordon sections to facilitate serpentine-like coilingof the chordons during their stroke to maintain adequate sealing withoutdetrimental binding.

FIGS. 19A and 19B are top views of a portion of a radial impulse engine1900 (“engine 1900”) having a plurality of hinged chordons 1940 a-dconfigured in accordance with another embodiment of the invention. Inthis embodiment, each of the chordons 1940 includes a body portion 1941and a corresponding hinged extension 1942. A drag link 1943 can beoperably coupled to each of the hinged extensions 1942 to controlmovement of the hinged extensions 1942 as the chordons 1940 pivotoutwardly from the top dead center position illustrated in FIG. 19A tothe bottom dead center position illustrated in FIG. 19B.

FIGS. 20A and 20B are cross-sectional end views of a telescoping chordon2040 configured in accordance with an embodiment of the invention. FIG.20A shows the chordon 2040 in a retracted position (e.g., a bottom deadcenter position), and FIG. 20B shows the chordon 2040 in an extendedposition (e.g., a top dead center position). Referring to FIGS. 20A and20B together, the chordon 2040 can include a body portion 2047 thatslides back and forth on a base portion 2049. A control link 2043,having a fixed pivot point 2045, controls the position of the bodyportion 2047 relative to the base portion 2049 as the chordon 2040pivots about a wrist shaft 2020. Specifically, when the chordon 2040pivots in a counterclockwise direction, the control link 2043 causes thebody portion 2047 to move away from the wrist shaft 2020, therebyincreasing the length of the chordon 2040. Conversely, when the chordon2040 pivots in a clockwise direction, the control link 2043 causes thebody portion 2047 to move toward the wrist shaft 2020, therebydecreasing the length of the chordon 2040. Those of ordinary skill inthe relevant art will appreciate that the control link configurationdescribed above is but one possible mechanism for controlling chordonlength. Accordingly, in other embodiments, other control linkconfigurations and/or other mechanisms can be used to vary chordonlength during engine operation.

FIG. 21 is a cross-sectional end view of a telescoping chordon 2140configured in accordance with another embodiment of the invention. Inthis embodiment, the chordon 2140 includes a coil spring 2143 compressedbetween a body portion 2147 and a corresponding base portion 2149. Asthe chordon 2140 sweeps through its arc during engine operation, thecoil spring 2143 presses the body portion 2147 against the adjacentchordon surface, thereby maintaining a sufficient seal withoutdetrimental binding or gaps.

Telescoping chordons configured in accordance with other embodiments ofthe invention can include other means for controlling chordon lengthduring engine operation. Such means can include, for example, hydraulicand/or pneumatic systems that function in a manner that is at leastgenerally similar to the coil spring 2143 described above. Telescopingchordons such as those described above with reference to FIGS. 20A-21can be utilized in a number of different engine configurations where avariable chordon length is required or desirable. Such engineconfigurations can include, for example, the engines 1800 and 1900described above with reference to FIGS. 18A-19B.

III. Valve Actuation

FIG. 22 is a side view of a portion of a radial impulse engine 2200(“engine 2200”) illustrating a system for poppet valve actuation inaccordance with an embodiment of the invention. The engine 2200 can beat least generally similar in structure and function to the engine 100described above with reference to FIGS. 1-4E. For example, the engine2200 can include a plurality of intake and/or exhaust valves 2230 heldclosed by a plurality of corresponding coil springs 2234. In thisparticular embodiment, however, the engine 2200 further includes a camlobe 2264 fixedly attached to a distal end of an extended wrist shaft2220. A rocker arm 2260 pivotally extends between the cam lobe 2264 anda valve actuator plate 2236. During engine operation, the pivoting camlobe 2264 causes the rocker arm 2260 to intermittently press against theactuator plate 2236, thereby compressing the valve springs 2234 andtemporarily opening the poppet valves 2230. In other embodiments of thepresent invention, valve actuation can be performed by other parts ofthe engine 2200. In one other embodiment, for example, a valve-actuatingcam lobe or cam lobes can be driven off of a synchronizing ring gear(e.g., one of the ring gears 228 of FIG. 2).

FIG. 23 illustrates a valve actuation system configured in accordancewith another embodiment of the invention. In this embodiment, a radialimpulse engine 2300 (“engine 2300”) includes a cylindrical ring cam 2364configured to rotate about an engine center axis 2301. The ring cam 2364can be driven in a number of different ways. In one embodiment, forexample, the ring cam 2364 can be driven off of a wrist shaft gear (notshown). In another embodiment, the ring cam 2364 can be driven off of asynchronizing ring gear (e.g., a ring gear at least generally similar instructure and function to the ring gears 228 of FIG. 2). The ring cam2364 includes a plurality of cam lobes 2366 a-b that depress and openadjacent poppet valves 2330 as the ring cam 2364 rotates about thecenter axis 2301.

If symmetrical valve opening/closing profiles are desired, then the camlobes 2366 should have correspondingly symmetrical shapes. In suchembodiments, the ring cam 2364 can rotate unidirectionally orreciprocate back and forth. Alternatively, if an asymmetrical valveopening/closing profile is desired, then the cam lobes 2366 should havea correspondingly asymmetrical shape, and the ring cam 2364 should beconfigured to rotate unidirectionally about the center axis 2301.

FIG. 24 is an isometric view of a portion of a radial impulse engine2400 (“engine 2400”) illustrating a method for controlling the flow ofgaseous mixtures into and out of an associated combustion chamber 2403.In one aspect of this embodiment, the engine 2400 includes a scavengingbarrel 2402 extending between a first end plate 2404 a and a second endplate 2404 b. The scavenging barrel 2402 includes a plurality of intakeports 2426 a-f configured to admit an air/fuel mixture into thescavenging barrel 2402. One or both of the end plates 2404 can include aplurality of exhaust ports 2432 a-f configured to discharge exhaustgases from the combustion chamber 2403.

In another aspect of this embodiment, the engine 2400 further includes acylindrical sleeve valve 2462 and a series of shutter valves 2466 a-f.The sleeve valve 2462 is concentrically disposed around the exterior ofthe scavenging barrel 2402, and includes a plurality of apertures 2464a-f. In operation, the sleeve valve 2462 rotates about an engine centeraxis 2401 to vary the position of the apertures 2464 relative to theintake ports 2426 and control the flow of the air/fuel mixture into thescavenging barrel 2402. In one embodiment, movement of the sleeve valve2462 can be controlled through gear engagement with one or more of aplurality of wrist shafts 2420 a-f. In other embodiments, movement ofthe sleeve valve 2462 can be controlled by other means. In theillustrated embodiment, the shutter valves 2466 are operably coupled tothe wrist shafts 2420. In operation, the shutter valves 2466 rotate backand forth with the wrist shafts 2420 to open and close the exhaust ports2432 at the appropriate times during chordon stroke.

FIG. 25 is a partially hidden top view of a portion of a radial impulseengine 2500 (“engine 2500”) having a movable valve plate 2566 thatoverlays an engine end plate 2504. In this embodiment, the engine endplate 2504 includes a plurality of shaped exhaust ports 2532 a-f whichopen into a combustion chamber 2503. The valve plate 2566 includes aplurality of corresponding apertures 2567 a-f. In operation, the valveplate 2566 rotates back and forth (or unidirectionally) about an enginecenter axis 2501 to position the apertures 2567 over the exhaust ports2532 at the appropriate times during chordon stroke.

IV. Power Take Out

A portion of the discussion above directed to FIG. 2 described onemethod for taking power out of a radial impulse engine, namely, byoperably coupling the wrist shafts to a crankshaft via one or moreconnecting rods. In other embodiments of the invention, however, othermethods can be used to take power out of the radial impulse enginesdescribed above.

FIG. 26, for example, is a top view of a radial impulse engine 2600having a cam plate 2674 for transmitting power from a plurality ofchordons 2640 a-f to an output shaft 2678. In this embodiment, a torquearm 2622 a-f is fixedly attached to each chordon wrist shaft 2620 a-f. Acam follower 2624 a-f positioned on the distal end of each torque arm2622 rollably engages a cam track 2676 in the cam plate 2674. Inoperation, the torque arms 2622 move with the chordons 2640 so that whenthe chordons 2640 pivot outwardly during the power stroke, the camfollowers 2624 move inwardly and drive the cam plate 2674 in acounterclockwise direction about an engine center axis 2601. At the endof the power stroke, the momentum of the rotating cam plate 2674 drivesthe chordons 2640 back toward the top dead center position forcompression and ignition of the next intake charge.

FIG. 27A is a partially cutaway isometric view of a radial impulseengine 2700 that uses a duplex synchronization gear 2728 fortransmitting power from a plurality of chordons 2740 a-f. FIG. 27B is across-sectional view taken through a wrist shaft 2720 of FIG. 27A.Referring to FIGS. 27A and 27B together, the synchronization gear 2728has a channel shape with an inner flange 2730 and an outer flange 2731.The inner flange 2730 includes a plurality of equally spaced-apart innerteeth groups 2732 a-f. The outer flange 2731 similarly includes aplurality of equally spaced-apart outer teeth groups 2733 a-f. Each ofthe wrist shafts 2720 a-f carries a first timing gear 2721 and a secondtiming gear 2722. The first timing gears 2721 are configured tosequentially engage the inner teeth groups 2732, and the second timinggears 2722 are configured to sequentially engage the outer teeth groups2733.

In operation, the synchronization gear 2728 rotates in one direction(e.g., a clockwise direction) about an engine center axis 2701. When thechordons 2740 begin moving outwardly from the top dead center positionon the power stroke, the first timing gears 2721 engage the inner teethgroups 2732 of the synchronization gear 2728, thereby driving thesynchronization gear 2728 in the clockwise direction. When the chordons2740 reach the bottom dead center position, the first timing gears 2721disengage from the inner teeth groups 2732 and the second timing gears2722 simultaneously engage the outer teeth groups 2733. The momentum ofthe rotating synchronization gear 2728 then drives the chordons 2740back inwardly toward the top dead center position. Thus, as thesynchronization gear 2728 rotates about the center axis 2701, italternates between receiving power pulses from the chordons 2740 via thefirst timing gears 2721 and driving the chordons 2740 back toward thetop dead center position via the second timing gears 2722. Accordingly,the wrist shafts 2720 oscillate back and forth while the synchronizationgear rotates unidirectionally to maintain flywheel effect.

FIG. 28 is an isometric view of a portion of a power unit 2805 having afirst radial impulse engine 2800 a operably coupled to a second radialimpulse engine 2800 b in accordance with an embodiment of the invention.The radial impulse engines 2800 of this embodiment can be at leastgenerally similar in structure and function to one or more of the radialimpulse engines described in detail above. For example, the first engine2800 a can include a plurality of first chordons 2840 a, and the secondengine 2800 b can include a plurality of second chordons 2840 b. Thefirst chordons 2840 a are operably coupled to the second chordons 2840 bby means of a gear set 2880 a-b.

In this particular embodiment, the first chordons 2840 a operatecounter-cyclically with respect to the second chordons 2840 b. That is,the first chordons 2840 a are at a bottom dead center position when thesecond chordons 2840 b are at a top dead center position. One advantageof this embodiment is that counter-cyclic operation can enable the powerunit 2805 to provide constant, or near-constant, torque output.

V. Power Unit Configurations

FIG. 29 is an isometric view of a portion of a power unit 2905configured in accordance with another embodiment of the invention. Inthis embodiment, the power unit 2905 includes a first radial impulseengine 2900 a coaxially coupled to a second radial impulse engine 2900b. The radial impulse engines 2900 can be at least generally similar instructure and function to one or more of the radial impulse enginesdescribed in detail above. For example, the first engine 2900 a caninclude a plurality of first chordons 2940 a, and the second engine 2900b can include a plurality of second chordons 2940 b.

In this particular embodiment, however, the power unit 2905 furtherincludes a plurality of extended wrist shafts 2920 (identifiedindividually as wrist shafts 2920 a-f) extending through a mid-plate2904. The wrist shafts 2920 carry the first chordons 2940 a of the firstengine 2900 a as well as the second chordons 2940 b of the second engine2900 b. The second chordons 2940 b, however, are inverted relative tothe first chordons 2940 a so that the second engine 2900 b operatescounter-cyclically relative to the first engine 2900 a. Specifically, asthe wrist shafts 2920 rotate in a counterclockwise direction, the firstchordons 2940 a pivot from a top dead center position toward a bottomdead center position while the second chordons 2940 b pivot inwardlyfrom a bottom dead center position toward a top dead center position. Asmentioned above with reference to FIG. 28, this counter-cyclic operationenables the power unit 2905 to provide constant, or near-constant,torque output.

FIG. 30 is a partially schematic side view of a power unit 3005configured in accordance with a further embodiment of the invention. Inthis embodiment, the power unit 3005 includes a radial impulse engine3000 (“engine 3000”) operably coupled to a first radial compressor 3010a and a second radial compressor 3010 b. The compressors 3010 arecoaxially aligned with the engine 3000. Further, each of the compressors3010 includes a plurality of chordons (not shown) operably coupled to aplurality of corresponding chordons (also not shown) in the engine 3000by means of extended wrist shafts 3020 (identified individually as wristshafts 3020 a-f). As described in greater detail below with reference toFIGS. 31A-31C, in operation, the compressors 3010 pump compressed airinto the engine 3000 via a first intake port 3031 a and an oppositesecond intake port 3031 b. The compressed air is then mixed with fueland ignited in the engine 3000 before being discharged through aplurality of exhaust ports 3030 a-f.

FIGS. 31A-31C are a series of top views illustrating a method ofoperating the power unit 3005 of FIG. 30 in accordance with anembodiment of the invention. Referring first to FIG. 31A, the engine3000 includes a plurality of engine chordons 3140 operably coupled tothe extended wrist shafts 3020. The first compressor 3010 a includes aplurality of first compressor chordons 3141 a operably coupled to theextended wrist shafts 3020, and the second compressor 3010 b similarlyincludes a plurality of second compressor chordons 3141 b operablycoupled to the extended wrist shafts 3020. The compressor chordons 3141are inverted with respect to the engine chordons 3140 so thatcompressors 3010 operate counter-cyclically with respect to the engine3000.

Operation of the power unit 3005 can begin by ignition of an intakecharge in the engine 3000 when the engine chordons 3140 are in a topdead center position as illustrated in FIG. 31A. The resultingcombustion drives the engine chordons 3140 outwardly, causing the wristshafts 3020 to rotate in a counterclockwise direction. This wrist shaftrotation drives the compressor chordons 3141 of the first and secondcompressors 3010 inwardly toward a top dead center position. As thecompressor chordons 3141 move inwardly, they drive the air in theirrespective chambers into the engine 3000 via the first and second intakeports 3031 (FIG. 30). When the engine chordons 3140 reach the bottomdead center position as illustrated in FIG. 31B, the exhaust gases areallowed to flow out of the engine 3000 via the exhaust ports 3030 (FIG.30). The incoming air from the adjacent compressors 3010 helps to drivethe exhaust gases out of the engine 3000.

Referring next to FIG. 31C, the intake ports 3031 (FIG. 30) close as theengine chordons 3140 move inwardly from the bottom dead center positiontoward the top dead center position. As a result, the intake charge iscompressed in the engine 3000. Simultaneously, the compressor chordons3141 of the adjacent compressors 3010 move outwardly from theirrespective top dead center positions to bottom dead center positions, inthe process drawing new air into their respective combustion chambers.At this time, fuel is mixed with the intake charge in the engine 3000and ignited, causing the cycle described above to repeat.

Although various aspects of the invention described above are directedto internal combustion engines, in other embodiments, other aspects ofthe invention can be directed to other types of power units, including,for example, steam engines, diesel engines, hybrid engines, etc.Furthermore, in yet other embodiments, other aspects of the inventioncan be directed to other types of useful machines, including pumps(e.g., air pumps, water pumps, etc.), compressors, etc.

VI. Radial Impulse Steam Engines

FIGS. 32A and 32B are top views of a radial impulse steam engine 3200(“steam engine 3200”) configured in accordance with an embodiment of theinvention. Referring first to FIG. 32A, the steam engine 3200 includes aplurality of chordons 3240 a-f movably disposed between a first endplate 3204 a and a second end plate 3204 b. An intake valve 3231 ispositioned in the first end plate 3204 a, and an exhaust valve 3230 ispositioned in the second end plate 3204 b.

In operation, the intake valve 3231 opens and admits steam into anexpansion chamber 3203 when the chordons 3240 are in the top dead centerposition of FIG. 32A. The intake valve 3231 then closes as the steamexpands, driving the chordons 3240 outwardly. As the chordons 3240 moveoutwardly, the exhaust valve 3230 begins to open, allowing the steam toflow out of the expansion chamber 3203. When the chordons 3240 reach thebottom dead center position of FIG. 32B, the exhaust valve 3230 is fullyopen.

As the chordons 3240 begin to move inwardly from the bottom dead centerposition, the exhaust valve 3130 starts to close. When the chordons 3240reach the top dead center position of FIG. 32A, the exhaust valve 3230is fully closed. At this time, the cycle repeats as the intake valve3231 opens, admitting a fresh charge of steam into the expansion chamber3203.

Although FIGS. 32A and 32B illustrate only a single intake valve 3231and a single exhaust valve 3230, in other embodiments, steam enginesconfigured in accordance with the present invention can include one ormore intake valves and/or one or more exhaust valves. Further, inanother embodiment of the invention, two steam engines at leastgenerally similar in structure and function to the steam engine 3200 canbe counter-cyclically coupled together to provide constant, ornear-constant, torque output.

FIGS. 33A and 33B are top views of a radial impulse steam engine 3300(“steam engine 3300”) configured in accordance with another embodimentof the invention. Referring to FIGS. 33A and 33B together, the steamengine 3300 includes a plurality of chordons 3340 a-f movably disposedbetween a first end plate 3304 a and a second end plate 3304 b. A barrel3302 extends around the chordons 3340 between the first and second endplates 3304. In this particular embodiment, a first intake valve 3331 ispositioned at the center of the first end plate 3304 a, and a pluralityof second intake valves 3333 a-f are positioned toward the outerperimeter of the first end plate 3304 a. In addition, a plurality ofexhaust valves 3330 a-f are positioned in the second end plate 3304 bapproximately equidistant between the center of the steam engine 3300and the outer perimeter of the second end plate 3304 b.

In operation, the first intake valve 3331 opens and admits steam into anexpansion chamber 3303 when the chordons 3340 are in the top dead centerposition shown in FIG. 33A. The first intake valve 3331 then closes,allowing the steam to expand and drive the chordons 3340 outwardlytoward the bottom dead center position shown in FIG. 33B. As thechordons 3340 move past the exhaust valves 3330, the exhaust valves 3330open, allowing the steam to flow out of the expansion chamber 3303.

When the chordons 3340 reach the bottom dead center position shown inFIG. 33B, the second intake valves 3333 open, admitting a fresh chargeof steam into the space between the chordons 3340 and the barrel 3302.The second intake valves 3333 then close, allowing this steam to expandand drive the chordons 3340 inwardly toward the top dead center positionof FIG. 33A. As the chordons 3340 move inwardly, the exhaust valves 3330close to avoid contact. When the chordons 3340 reach the top dead centerposition of FIG. 33A, the exhaust valves 3330 again open, allowing thepressurized steam behind the chordons 3340 to escape. At this time, thecycle repeats as the first intake valve 3331 opens, admitting a freshcharge of steam into the expansion chamber 3303.

From the foregoing, it will be appreciated that specific embodiments ofthe invention have been described herein for purposes of illustration,but that various modifications may be made without deviating from thespirit and scope of the invention. For example, aspects of the inventiondescribed in the context of particular embodiments may be combined oreliminated in other embodiments. Further, while advantages associatedwith certain embodiments of the invention have been described in thecontext of those embodiments, other embodiments may also exhibit suchadvantages, and not all embodiments need necessarily exhibit suchadvantages to fall within the scope of the invention. Accordingly, theinvention is not limited, except as by the appended claims.

1. An engine comprising: a first end wall portion; a second end wallportion spaced apart from the first end wall portion to at leastpartially define a pressure chamber therebetween; a first movable wallportion operably disposed between the first and second end wallportions, the first movable wall portion being pivotable about a firstpivot axis and having a first surface facing at least generally towardthe pressure chamber; a second movable wall portion operably disposedbetween the first and second end wall portions adjacent to the firstmovable wall portion, the second movable wall portion being pivotableabout a second pivot axis and having a second surface facing at leastgenerally toward the pressure chamber; and a synchronizing apparatusoperably coupling the first movable wall portion to the second movablewall portion, the synchronizing mechanism causing the first and secondmovable walls to move in unison as the first movable wall portion pivotsabout the first pivot axis and the second movable wall portion pivotsabout the second pivot axis.
 2. The engine of claim 1, furthercomprising a third movable wall portion operably disposed between thefirst and second end wall portions, wherein the synchronizing apparatusoperably couples the first movable wall portion to the second and thirdmovable wall portions.
 3. The engine of claim 1, wherein thesynchronizing apparatus includes a gear operably coupling the firstmovable wall portion to the second movable wall portion.
 4. The engineof claim 1, further comprising a third movable wall portion operablydisposed between the first and second end wall portions, and wherein thesynchronizing apparatus includes a gear operably coupling the firstmovable wall portion to the second and third movable wall portions. 5.The engine of claim 1, further comprising: a first wrist shaftconfigured to pivot about the first pivot axis; and a second wrist shaftconfigured to pivot about the second pivot axis, wherein the firstmovable wall portion is fixedly attached to the first wrist shaft andthe second movable wall portion is fixedly attached to the second wristshaft, and wherein the synchronizing apparatus operably engages thefirst and second wrist shafts.
 6. The engine of claim 1, furthercomprising: a first wrist shaft configured to pivot about the firstpivot axis; a second wrist shaft configured to pivot about the secondpivot axis; a first timing gear fixedly attached to the first wristshaft; and a second timing gear fixedly attached to the second wristshaft, wherein the first movable wall portion is fixedly attached to thefirst wrist shaft and the second movable wall portion is fixedlyattached to the second wrist shaft, and wherein the synchronizingapparatus includes a gear operably engaging the first and second timinggears.
 7. The engine of claim 1, further comprising a third movable wallportion operably disposed between the first and second end wallportions, the third movable wall portion being pivotable about a thirdpivot axis, wherein the first, second, and third pivot axes define acircle, and wherein the synchronizing apparatus includes a ring gearconfigured to rotate about an axis extending through a center of thecircle.
 8. The engine of claim 1, further comprising: a first wristshaft fixedly attached to the first movable wall portion and configuredto pivot about the first pivot axis; a second wrist shaft fixedlyattached to the second movable wall portion and configured to pivotabout the second pivot axis; a third wrist shaft fixedly attached to athird movable wall portion and configured to pivot about a third pivotaxis; a first timing gear fixedly attached to the first wrist shaft; asecond timing gear fixedly attached to the second wrist shaft; and athird timing gear fixedly attached to the third wrist shaft, wherein thefirst, second, and third pivot axes define a circle, and wherein thesynchronizing apparatus includes a ring gear configured to rotate aboutan axis extending through a center of the circle.
 9. The engine of claim1, further comprising: a first wrist shaft fixedly attached to the firstmovable wall portion and configured to pivot about the first pivot axis;a second wrist shaft fixedly attached to the second movable wall portionand configured to pivot about the second pivot axis; and a crankshaft,wherein the synchronizing apparatus includes a gear operably engagingthe first wrist shaft with the second wrist shaft, and wherein thecrankshaft is operably coupled to the gear and configured to rotateunidirectionally as the first movable wall portion pivots about thefirst pivot axis and the second movable wall portion pivots about thesecond pivot axis.
 10. The engine of claim 1, further comprising a thirdmovable wall portion operably disposed between the first and second endwall portions, the third movable wall portion being pivotable about athird pivot axis, wherein the first, second, and third pivot axes definea circle having a first radius of curvature, and wherein the secondsurface of the second movable wall portion has a second radius ofcurvature that is at least approximately equivalent to the first radiusof curvature.
 11. The engine of claim 1 wherein the first movable wallportion further includes a first distal edge portion spaced apart fromthe first pivot axis, and wherein the first distal edge portion isconfigured to slide across the second surface of the second movable wallportion as the first movable wall portion pivots about the first pivotaxis and the second movable wall portion pivots about the second pivotaxis.
 12. The engine of claim 1 wherein the first movable wall portionfurther includes a distal edge portion spaced apart from the first pivotaxis, and wherein the distal edge portion of the first movable wallportion carries a seal configured to slide across the second surface ofthe second movable wall portion as the first movable wall portion pivotsabout the first pivot axis and the second movable wall portion pivotsabout the second pivot axis.
 13. The engine of claim 1 wherein the firstmovable wall portion further includes a distal edge portion spaced apartfrom the first pivot axis, wherein the distal edge portion of the firstmovable wall portion is configured to lubricate the second surface ofthe second movable wall portion as the distal edge portion slides acrossthe second surface.
 14. The engine of claim 1 wherein the pressurechamber is a combustion chamber, and wherein the second movable wallportion includes an aperture configured to admit at least one of air andan air/fuel mixture into the combustion chamber.
 15. The engine of claim1 wherein the pressure chamber is a combustion chamber, and wherein theengine further comprises a fuel injector configured to spray fuel intothe combustion chamber.
 16. The engine of claim 1, wherein the pressurechamber is a combustion chamber, and wherein the engine furthercomprises an igniter configured to ignite an air/fuel mixture in thecombustion chamber.
 17. The engine of claim 1, wherein the pressurechamber is a combustion chamber, and wherein the engine furthercomprises valve configured to discharge exhaust gas from the combustionchamber.
 18. The engine of claim 1, wherein the pressure chamber is anexpansion chamber, and wherein the engine further comprises a valveconfigured to admit pressurized steam into the expansion chamber.
 19. Aninternal combustion engine comprising: a first end wall portion; asecond end wall portion spaced apart from the first end wall portion toat least partially define a combustion chamber therebetween; a firstwrist shaft extending at least partially between the first and secondend wall portions along a first pivot axis; a second wrist shaftextending at least partially between the first and second end wallportions along a second pivot axis; a first movable wall portion fixedlyattached to the first wrist shaft and having a first surface facing atleast generally toward the combustion chamber; a second movable wallportion fixedly attached to the second wrist shaft and having a secondsurface facing at least generally toward the combustion chamber; and asynchronizing apparatus operably coupling the first wrist shaft to thesecond wrist shaft, the synchronizing mechanism causing the first andsecond movable walls to move in unison as the first movable wall portionpivots about the first pivot axis and the second movable wall portionpivots about the second pivot axis.
 20. The engine of claim 19, whereinthe synchronizing apparatus includes a gear operably coupling the firstwrist shaft to the second wrist shaft. 21-36. (canceled)